start many informer,pod resourceVersion will duplicate base64。

[niuyueyang1996]

What happened:
when i start two or more informer,i see pod resourceVersion changed
1.659432795
2.eyJ3eC10ZXN0IjoiNjU5NDMyNzk1In0
{"wx-test":"659432795"}
3.eyJ3eC10ZXN0IjoiZXlKM2VDMTBaWE4wSWpvaU5qVTVORE15TnprMUluMCJ9
{"wx-test":"eyJ3eC10ZXN0IjoiNjU5NDMyNzk1In0"}

if i list pod,pod resourceVersion is number,like 659432795,i don't understand why not use base64 code?

if i start one watcher to watch pod ,pod resourceVersion is base64 code like eyJ3eC10ZXN0IjoiNjU5NDMyNzk1In0

if i start more than one watcher to watch pod,pod resourceVersion maybe is wrong base64 code like eyJ3eC10ZXN0IjoiZXlKM2VDMTBaWE4wSWpvaU5qVTVORE15TnprMUluMCJ9. this is bug.

What you expected to happen:
list pod resourceVersion is base64.
start more than one watcher to wach pod,pod resourceVersion only base64 one times.

How to reproduce it (as minimally and precisely as possible):

Anything else we need to know?:

Environment:

• Karmada version:
• kubectl-karmada or karmadactl version (the result of kubectl-karmada version or karmadactl version):
• Others:

[XiShanYongYe-Chang]

Thanks~, In favor of #3376
/assign @niuyueyang1996

[ikaven1024]

if i list pod,pod resourceVersion is number,like 659432795,i don't understand why not use base64 code?

Yes, we only convert the resourceVersion in List, not items. Such as:

kind: PodList
apiVersion: v1
metadata:
    resourceVersion:    <= converted RV
items:
  - metadata:
        name: pod1
        resourceVersion:     <= original RV

Mostly we use the List rv, rather than item rv, such as List&Watch. So we don't convert it.

If you have the case using rv in items, welcome your pr to supplement it.

[niuyueyang1996]

when i use informer.
first will list all resource, all resource resourceVersion is number.
after some resource change, watch event will make resourceVersion be base64code.
if i use resourceVersion to sort resource, the resourceVersion will inconsistent.

[ikaven1024]

if i use resourceVersion to sort resource, the resourceVersion will inconsistent.

In k8s doc https://kubernetes.io/docs/reference/using-api/api-concepts/#resource-versions:
You must not assume resource versions are numeric or collatable. API clients may only compare two resource versions for equality (this means that you must not compare resource versions for greater-than or less-than relationships).

[niuyueyang1996]

if i use resourceVersion to sort resource, the resourceVersion will inconsistent.

In k8s doc https://kubernetes.io/docs/reference/using-api/api-concepts/#resource-versions: You must not assume resource versions are numeric or collatable. API clients may only compare two resource versions for equality (this means that you must not compare resource versions for greater-than or less-than relationships).

if i use informer like informers.NewSharedInformerFactory(clientset, time.Second*30).
the informer will list all resource 30 seconds.
example:
pod a resourceVersion 1
1.first list resourceVersion is 1
2.pod change resourceVersion is 2 with base64Encode
3.second list pod resourceVersion change to 2.

step2 to step3, pod without resourceVersion change,but client receive resourceVersion is changed

[ikaven1024]

I will test it at my free time. Thanks for your feedback.

[XiShanYongYe-Chang]

Hi @niuyueyang1996, with the integration of #3376 , the current issue is closed.

For the get/list resourceVersion, you can create an issue to trace the issue.

[niuyueyang1996]

if i use informer like informers.NewSharedInformerFactory(clientset, time.Second*30). the informer will list all resource 30 seconds. example: pod a resourceVersion 1 1.first list resourceVersion is 1 2.pod change resourceVersion is 2 with base64Encode 3.second list pod resourceVersion change to 2.

step2 to step3, pod without resourceVersion change,but client receive resourceVersion is changed

#3382